Ethylene oxide polymerization

Dimethyl sulfoxide can also be used as a reaction solvent for other polymerizations. Ethylene oxide is rapidly and completely polymerized in DMSO (85). Diisocyanates and polyols or polyamines dissolve and react in DMSO to form solutions of polyurethanes (86) (see Solvents, industrial). 

Nuclear Magnetic Resonance (nmr). The nmr analysis has been used in the polymer industry for some time to measure properties such as amount and type of branching, polymerized ethylene oxide content, and hydroxyl content. The same techniques are applicable to waxes, and are used for both characterization and quality control. 

Polyacetals are among the aliphatic polyether family and are produced by the polymerization of formaldehyde. They are termed polyacetals to distinguish them from polyethers produced by polymerizing ethylene oxide, which has two -CH2- groups between the ether group. The polymerization reaction occurs in the presence of a Lewis acid and a small amount of water at room temperature. It could also be catalyzed with amines ... 

Figure I indicates the approach used to synthesize poly(oxyethylene)-b-poly(pivalolactone) telechelomers. An acetal capped anionic initiator, X (13) polymerizes ethylene oxide (EO) to give 2> a potassium alkoxide of a masked polyether, and this "new" initiator is to be used to polymerize pivalolactone (PVL). Since potassium alkoxides are strong nucleophiles, they can randomly attack at both the carbonyl carbon and the 3-methylene carbon in lactones, (Figure 2) such a random attack would result in a pivalolactone segment containing irregularities. Lenz (15), and Hall (16), and Beaman (17) have investigated PVL polymerization and have shown that the less nucleophilic carboxylate anion is preferable in polymerizing PVL smoothly. The weaker carboxylate anion will attack only at the methylene...

Many other cyclic ethers have been polymerized using cationic polymerization. Ethylene oxide (also called oxirane) polymerizes forming poly(ethylene oxide) (PEO) (structure 5.24) in the presence of acids such as sulfuric acid, producing a wide range of chain-sized polymers sold under various trade names including Carbowax and Poly ox. PEO is also used in cosmetics and pharmaceuticals (as water-soluble pill coatings and capsules). 

Graft copolymers were prepared by polymerizing ethylene oxide onto the PVN polyradical anion (10), The latter was obtained by reaction of PVN with cesium in tetrahydrofuran solution. The copolymers were extracted with water to remove the PEO homopolymer which was formed as a byproduct. Experimental details and evidence for bond formation between ethylene oxide and the aromatic moiety were presented elsewhere (//). 

This is a composite of 1 % cross-linked polystyrene and covalently attached polyethylene glycol (PEG) (2000-3000 Da). One form, sold under the name TentaGel (Rapp Polymere), is made by polymerizing ethylene oxide on to a primary alcohol located on the cross-linked polystyrene [22,23], A second form, sold under the name PEG-PS (Perseptive), is made by attaching, through the formation of an amide bond, an already formed amino terminal PEG chain (Jeffamine) to 1% cross-linked polystyrene [24], The loading capacities for both types of supports are typically in the range of 0.2-0.3 mmol amine/g resin. 

Polyethylene oxide is prepared by the polymerization ethylene oxide using a suitable catalyst. ... 

Materials Determination of the Polymerized Ethylene Oxide Content of Polyester Polyols, 5 pp (Comm D-20)... 

K. Brzezinska, et al., Activated monomer mechanism in cationic polymerization ethylene-oxide, formulation of mechanism. Makromol. Chem. Rapid Commun. 1986, 7(1), 14-. 

In the same time period of Price s work, Hill, Bailey and Fitzpatrick of Union Carbide Corporation developed some improved catalysts for polymerizing ethylene oxide to high polymer(l ). These new catalysts included improvements on the very early systems of Staudinger, i.e., strontium, calciiom, and zinc oxides and carbonates, as well as some new, even better, systems based on calcium alkoxides(ii) and amides(j . Bailey used the latter systems in 1958 to make water-soluble ethylene oxide-unsaturated epoxide copolymers(17). Vulcanizates of these copolymers were very water sensitive and thus not very useful in the conventional elastomer area. 

Since this fluorescent labeling methodology is a living functionalization reaction, the resulting living fluorescent-labeled polymers can be used to initiate the polymerization of a second monomer to produce a block copolymer with the label at the block interface as discussed previously. For example, this procedure has been used to prepare polystyrene-Wock-poly(ethylene oxide) copolymers with both pyrene (60) (see Scheme 23) and naphthalene fluorescent groups at the interface between the two blocks [180-182]. Lithium was used as the counterion to prepare well-defined, quantitatively-ethylene oxide-functionalized polystyrenes in benzene solution [183]. However, under these conditions, it is not possible to polymerize ethylene oxide [183]. Therefore, it was necessary to add either dimethylsulfoxide [180, 181] or a potassium alkoxide [182] to promote ethylene oxide block formation as shown in Scheme 23. These diblock copolymers were fractionated to obtain pure diblock copolymer... 

Branched or star-block copolymers were made (187) by first polymerizing ethylene oxide onto a starter using cationic initiation. These compounds were then coupled with the diglycidyl ether of bisphenol A to increase molecular weight and to provide pendant hydroxyl group functionality in the central portions of the alkylene oxide/glycidyl epoxide copolymer. 

Nonionic, in which there are no electrical charges the hydrophobic group consists of alkylphenols, fatty alcohols, or fatty acids and is balanced by nonionized hydrophilic groups (e.g., polymerized ethylene oxide). 

American Society for Testing and Materials, Polymerized ethylene oxide content of polyether polyols, D4875. West Conshohocken, PA 19428. 

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